It is your vacation.... wear the kilt with what ever nice shirt you have. The crusie I went on had a formal night that we were supposed to wear blacktie yux or a suit to dinner that evening. I hate ties.

I paid a lot for the cruise so I wore what I felt appropriate for a tropical setting. My best Hawiaan shirt and nice slacks. (pre kilt era)

I got lots of comments from other uncomfortable men in their tuxs.